PREPARATION TECHNOLOGY OF (La,Ce,Tb)PO_4 USING COPRECIPITATION METHOD

摘要

Nitrates of La,Ce,Tb and (NH_4)_2HPO_4 are used to prepare (La,Ce,Tb)PO)4 crystals with good property using an improved coprecipitation method. A highly effective green fluorescent powder of phosphate is produced by calcinating the coprecipitated (La,Ce,Tb)PO_4. The effects of reaction temperature, feed liquid concentration, aging pH value, aging time, aging temperature and surfactant on the property of the precipitation granularity are discussed and the optimum technical conditions of coprecipitation is determined. The particle size, structure, morphology of the precipitation and the lightness of the fluorescent powder are measured by LGM, XRD, Microscope and SA respectively.